Wireless-signaling apparatus



No. 749,131. PATENTED JAN. 5 1904.

L. DB FOREST. WIRELESS SIGNALING APPARATUS.

APPLIOATION FILED DBO. 8, 1902.

N0 MODEL.

WITNESSES: v A q ggfll Z 0 A BY (7% I I ZJAIAT H/VEY LEE DE FonEs'r, OF N W YORK, N. Y..,

Patented January 5, 1904.

ATENT EEiciE.

ASSIGNOR TO WIRELESS TELEGRAPH COMPANY OF AMERICA, A CORPORATION OF NEW JERSEY.

WIRELES$=SIGNALING APPARATUS.

SPECIFICATION forming part of Letters ?atent No. 749.131, dated. January 5, 1904.

Original application filed March 6. 1901, Serial No. 60.078.

To all whom it may concern:

Be it known that I, LEE DE FOREST, a citizen of the UnitedStates, and a resident of the city of New York, borough of Manhattan,

in the county and State of New York, have invented certain new and useful Improvements in Wireless-Signaling Apparatus, of which the following is a specification.

My invention relates to an improvement in wireless-signalingapparatus designed,prima-' rily, to enable a directional or concentrating effect to be given the signaling-waves radiated, whereby their eifectiveness may he increased in any given direction and to similarly increase the effectiveness 'of receiving waves when placed in proper relation to the directionof their travel. My invention is also capable of indicating approximately the direction from which a signal is received.

This application isa division ,of an application for an improvement in'space telegraphy, Serial No. 50,078, filed March 6, 1901.

My invention comprises the novel features and parts and combinations thereof, which 2, will be hereinafter described, and particularly pointed out in the claims.

In the figures of the drawings accompany.- ing herewith I have illustrated an apparatus embodying my invention.

Figure 1 shows my invention embodied in a sending or transmitting apparatus. Fig. 2 shows my invention embodied in a receiving apparatus. y

In the accepted theory of the nature of electromagnetic waves in space and conducting bodies when the aerial conductor at the sending-station is charged lines of force radiate from the whole surface of such conductor in all directions and normal to such surface, and if the other side of the spark-gapis earthed or grounded (as is the common practice in apparatus of this nature) the lines of force radiatingfrom the surface of the aerial conductor traverse circular paths from such. con- 5 ductor and at their other ends rest upon or reach the surface of the earth, thus forming,

so to speak, semiepheres'with the aerial conductor as an axis. When' the spark passes across the spark-gap, the electrical charge in Divided and this application filed December 8, 1902. Serial (No model.)

the aerial or generating conductor oscillates or surges to and fro throughout the length of such conductor, the waves being reflected at the upper end of the conductor, at which point a static loop is formed. The other .or lower ends ofthese lines of force and which rest in the earth move outwardly from the center over the'surface of the earth in everwideningcircles. Oonsequeutlyanelectrical displacement oppositein sign to the electrical displacement at that instant traversing the 6o upright conductor thus travels outwardly with the velocity of light in all directions alike in the form of a circle'of ever-increasing di-' ameter with the conductor as an' axis, which Wave follows the surface of the earth or water, 6 finally reaching distant points or receivingstatious even when located far below the horizon. For a fuller description of the theory of the propagation of the field of force in the Ilertzian telegraph I refer to my article on this theme in the Electrical World and Him gt'nee-r of'May 17, 1902. In the practical operation of a wireless-signaling apparatus and in order to secure the greatest amount of'effioiency it is desirable toprovide means whereby the direction of propagation of the energy waves radiated from the generating aerial conductor at the transmitting-station may be coutrolled...and determined. I Referring to Fig. l, reference-sign A designates an aerial or radiating conductor. Instead, however, of directly connecting this conductor to ground through the spark-gap of its charging and discharging apparatus,

as has been-usual heretofore, I lead'oif from the base of such conductor an insulated horizontal wire 0a, conductor B. In practice I prefer to employ a length of vertical or aerial conductor A corresponding to one-quarter a 0' wave length and a length of horizontal conductor B corresponding to one-half a wave length.

By the arrangement above described where-- in ahorizontal insulated wire or conductor is employed and-ledoif in a particular direction from the aerial conductor, said horizon tal wire OI'VCQQQQGLOI' being arranged any propagation.

convenient distance above the surface of the earth and which at the end thereof farthest removed from the aerial conductor-is grounded either directly or through a spark-gap, as indicated at B, I have found that a condition is produced differing from the usual condition above described-tlralt is, I have found that the lines of force generated inthe a rial conductor by the surgings occuring th rein instead of radiating in all directions from such conductor are concentrated in the plane which contains the two wires or conductors A and B, and thus the plane of these condoctors or wires determines'the plane or direction of propagation of the energy waves which are radiated.

The charging apparatus may be of the usual or any suitable construction and arrangement. As illustrative of an operative embodiment of charging apparatus I have shown an induction-coil construction, wherein the terminals of the secondary coil F are respectively connected to the primary sparkloalls C D.

G designates the primary of the inductioncoil, in the circuit of which are arrangeda generator H and interrupter J, of anysuitable or usual character.

The charging apparatus may be connected to the aerial and direction-determining conductors at any desired or convenient point, and whileI have shown the primary or charging-spark terminals 0 D, respectively, connected to the adjacent ends of the conductors A and B, I do not desire to be limited or restricted to this location and arrangement. In the arrangement shown, however, it will be observed that before the spark occurs between the terminals or balls C D the vertical and horizontal wires or conductors will be charged oppositely, and consequently the lines of force joining these two charges will lie mainly in the plane determined by these wires or conductors, thus giving a direction of propagation to these waves, as well as con-- ceirtrating such waves in such direction of Then the spark occurs, the electrical surgings set up in the two wires or conductors find earth through the secondary spark-gap B. Consequently the resulting energy wave is in the form of a planepolarized wave with its direction of propagation lying in the direction of the length of the wire B, and having once acquired a direction of propagation such direction is maintained except as difi'usion affects the same as it progresses outwardly .over the surface of the earth or water.

If desired, and in order to still further define and determine the plane of propagation of the energy waves, a second wire (indicated in dotted lines at M) equal in length and par allel with respect to wire B maybe led off from the top end of the wire or'condnctor A. This arrangement also produces a more resonant system.

If desired, and in order to augment or latter.

crease the intensityof the radiated energy waves, instead of employing t'ne additional horizontal wire M an additional vertical conductor A may be employed, as indicated in dotted lines in Fig. 1, which conductor is equal in length'and arranged parallel with respect to conductor A and connected at the other end of the horizontal wire B in a manner similar to the connection of such wire to conductor A. In this arrangement it is preferred to have the charging apparatus con.- nected to the apparatus at a point midway the length of conductor 13, which in this case should be of a length corresponding to a halfwave length. In such event, however, a ground connection (indicated at E) should be provided for the lowerendofi the conductor A, which ground connection is reached through a spark-gap similar to the spark-gap B at the far end of conductor B, as is indicated by the dotted earth connection and spark-ball D. This spark-gap then becomes a secondary spark-gap and the primary spark-gap is moved to the central position between the conductors A and B. By thus s acing the two aerial conductorsA Aa half-w ve length apart the waves given oif or radiated from conductor A on arriving at a point conciding with conductor A serve to reinforce or augment the waves given off or radiated from the By revolving or shifting the position of the horizontal wire 8 about conductor A as a center it will be readily seen that the lines or direction of propagation of the radiated energy waves may be controlled.

If desired, and in order to increase the current represented by the electrical surgings in the conductors A and B. I may introduce in IOC said conductors and at a point adjacent to the nodes therein suitable condensers, as indicated at L, thereby effecting a, radiation of a larger amount of energy, and in order to secure the advantage of a longerduration of the electrical surgings in order to send out longer wave-trains with the same amount of energy I may also introduce in the conductors A and B at points adjacent to the nodes therein momentum-coils, as indicated at K.

By the construction and arrangement of transmitting apparatus above described I am enabled to eiii cienily determine the direction and plane of propagation of the energy-waves sent out. I am also enabled to control and govern such direction of propagation, so as to direct the same toward any particulardistant reccivirig-station. I also secure the advantage of a conctmtration of the radiated energy waves, thus increasing the range of the apparatus or the distance through which signals may be transmitted through space,

in- A to the best advantage, the cohercr or other be used.

sive device being connected to earth ip-at,

zero-potential. I y

In carrying out my invention I propose to employ two or a cooperating pair of aerial receiving or collecting conductors, in each of which stationary waves are produced by the cutting thereby of the lines of force or waves of energy radiated from the transmittingstation, as above explained, and I propose to so separate and place the collecting-conductors and the coherer or other wave-responsive device so that the latter will be located at a point where occurs aJoop of positive potential in the statienary waves of one receiving wire or conductor and a loop of negative potential in the stationary waves of the other receiving wire or conductor, thus securing conditions of maximum efficiency in the receiving device. Different arrangement for accomplishing this result may be employed. One arrangement is shown in Fig. 2, wherein reference sign A designates one of the aerial receiving or collecting conductors and A the other. These conductors should each be preferably one-qnarter-wave length in length and are spaced aparta distance of one-half-wave length. B designates the coherer or other wave-responsive device employed.

Any form of wave-responsive device may I have'shown a form of receiving. or Wave-responsive device of the anticoher'er type, which I have employed, wherein contact-points B B are employed and arranged in series in a wire or conductor connecting the aerialreceiving-conductors A A, a porous or other body B being interposed in series between the adjacent orproximate ends of contacts 13 B in order to support or maintain a fluid or other substancein the space between said contacts.

A designates the indicating device, herein shown as a telephoneweceiver, but may be of any suitable form. I

A isa local battery, and A suitable chokecoils. The choke-coils, the signal-indicating instrument A, the battery A, and the waveresponsive device, herein shown as consisting of the contacts B B are all arnmged in series in the local-battery circuit, the wave-responsive device being alsolocated in series with the aerial receiving-00nductors A A New by the arrangement above described and by respectively connecting the conductors A A at the lower ends thereof to earth at B B it will be seen that the electrostatic waves generated or produce. in the two verwhich tical receiving-conductors by the sign al-tran sanitizing-wave trains will have nodes at the I points a b and lines a 0 being graphic representations, respectively, of the positive and negative stationary waves having the point a as their node and reference-signs b b reprd ent'ingmimilarly and respectively, uegai ive 'anii'pos itive waves having the point b as their node. The'location of the wave-responsive device B at a point midway between the pointsn b will bring the terminals of such resistance device at points where occurs a loop of positive potential on one side and a loop of negative potential on the other side,and hence at a point where the maximum effect is secured and the greatest possible advantage derived.

By the usual practice, as previously pointed out, one terminal of the wave-responsive device being directly oonnected with the earth is at zero potentialfand the difference of potential between its terminals can thus be only half what it would be by my plan. This increased effect is produced in its maximum degree only when the plane which contains the aerial receiving-conductors A A coin- .cides with the plane of propagation of the energy waves radiated from the transmitt-i ngstation, as otherwise the stationary waves when they reach the wave-responsive device would not be opposite in phase; Any deviation of the plane of the receivingconductors A A from coinciding relation with respect to the direction of travel of the energy waves radiated will result in a decreased efficiency at the receiving-station and will be noticeable.

The arrangement above described, wherein the receiving-conductors are a quarter-wave lengthin length and arespaced one-half-wave length apart, affords means for detecting the direction from which proceeds the arriving energy waves, and by shifting, the plane of the receiving-conductors A A about a vertical axis the direction from which proceeds the. arriving energy waves may be determined. Thisis a point ofobvious importance in apparatus of this kind, and especially when employed for signaling at sea or on board ship. The shifting of the plane which contains and is determined by the two aerial receiving-conductors may be effected in any suit-able or convenient manner.

' Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

1. In wireless signaling the combination with a vertical and horizontal linear conductor connected in series with the earth, of a wave-producing device connected to synchronously produce electrical waves inboth of said conductors.

2. In a wireless signaling apparatus in combination, a radiating-antenna, a horizontal conductor of relatively small transverse ditenna and the earth and cooperating with said antenna to give a concentrating or directi'onalefiect to the waves radiated, and means 'mensions connected in series with the anfor producing synchronous oscillations in both of said conductors.

3. In wireless signaling, the combination with a vertical radiating-conductor and a horizontal linear conductor placed in series between the vertical conductor and the earth and extending from the vertical conductor in the. direction the signal is to be sent, and means for producing electrical Waves in the l0 aerial circuit thereby formed.

4. In wireless signaling, the combination with a vertical radiating-conductor equivalent in length to one-quarterof a wave length, a horizontal conductor equivalent in length to a multiple of a quarter of a wave length, said conductors being connected in series with the earth and means for synchronously setting up electrical oscillations in both said radiating-conductors. v

5. The means for giving a direction or concentratin g efiect to the radiations from a vertical conductor, comprising a horizontal conductor extending from said vertical conductor in the direction of the concentration desired, and adapted to participate with said vertical conductor in the electrical oscillations set up therein and a ground connection for the end of said horizontal conductor a multiple of a quarter-wave length from the- 50 vertical conductor.

6. In wireless signaling, the combination with a vertical and a horizontal linearconductor of a wave-prod uciug device, including a spark-gap having one ball connected with proximate ends of each of said conductors.

7. In wireless signaling, the combination with a vertical and a horizontal linear conductor, a waveproducing device connected with both of said conductors, and a common earth o connection for ,both of said conductors including therein a spark-gap.

8. In wireless signaling, the combination with a vertical radiating-conductor, and a horizontal conductor of means for producing oscillations in both conductors connected thereto at the base of the vertical conductor, ,and a common g'rou'nd connection for both located a half-wave length from the vertical conductor. 7

9. In wireless signaling, the combination with a vertical radiating-conductor and a horizontal conductor of means for producing oscillations in said conductors connected thereto at the base of the vertical conductor, and a common ground connection for both conductors connected with the horizontal conductor a half-wave length from the vertical conductor and containing a spark-gap.

10. In wireless signaling the combination with a horizontal conductor, two spark-gaps having one member of each connected respectively with opposite ends of said condoctor, a vertical radiating-conductor connected with the other member of one sparkgap, and an earth connection with the other member of the other spark-gap.

11. In wireless signaling apparatus, the

combination with two conductors angularly disposed with relation to each other and having, adjacent ends, of a wave producing mechanism connected with said conductors and having adjacent ends, one of said-conductors being equivalent in length to a quarter-wave length'and the other'equiva lent in length to a half-wave length of a wave-producing mechanism connected with both conductors at the apex of the angle therebetween, and a groundconnection to the longer conductor at its opposite end.

' 13. In a wireless signalingsystem, the combination with signal-wave producing and radiating device, of a receiving device comprising two wave-collecting conductors located a half-wave length apart in .the direction of travel of the received waves, and each provided with a ground connection, a conductor connecting said collecting-conductors and a wavea'esponsive device interposed midway in said connecting-conductor. 14-. In a wireless signaling system the combination with a signal-wave producing and radiating mechanism, of a receiving; de vice comprising two collecting-antennmseparated a halfwave length, each provided with a ground connection and being adapted to be swung about, a vertical axis, a conductor connecting their base and a signalindicating apparatus in said connecting-conductor midway its length,

15. In an apparatus of the classdescrihed,a horizontal conductor having spark g'aps at the ends thereof, the spark-gap at one end-of said conductor being connected to earth, an aerial conductor connected to one of the terminals of the sparlcgap at the other end of said horizontal conductor, and a generator of electric potential having its terminals respectively connected to the terminals of the said spar-kgap.

16. In an apparatus of the class described, an aerial conductor and a codporating horizontal cond uctorg in combination with asparkproducing apparatus connected to said conductors at a node or, neutral point of the waves therein, and condensers arranged in said conductors adjacent to such node or neutral point.

17. In an apparatus of the class described, an aerial conductor and a codperating horizontal conductor,in combination with a sparkprodncing' apparatus having the terminals thereof respectively connected to adjacent ends of said conductor, in combination with momentum coils in trod uced into said condnctors adjacentsuch terminal connections.

18. In an apparatus of the class described,

an aerial conductor and-a cooperating horizontal conductor and a spark-gap interposed between them, in combination with a generator of electric potential having the terminals thereof respectively connected to th said spark-balls, and momentum-coils an; condensers arranged in said conductors adjacent to said spark-gap.

19. In an apparatus of the class described-1. radiating-conductor in combination Witha. cooperating conductor arranged in rectangular relation with respect thereto, and means connected at the apex of the angle between said conductors adapted to produce electrical surging of opposite signs in said respective conductors.

20. In an apparatus of the class described, andiin combination with means'for determining the plane of propagation of energy waves, a receiving apparatus including two wave-collecting aerial conductors each provided with earth connections and spaced a half-wave length apart, a horizontal conductor connecting said aerial conductors and a receiving instrument so zontal conductor that a maximum of positive potential and a maximum of negative potential simultaneously occurs at the respective terminals thereof.

In testimony whereof I have hereunto atfixed my signature, this 4th day of Decemher, 1902, in the presence of two witnesses.

- LEE DE FOREST.

Witnesses:

H. L. REYNOLDS, JULIA M. MOLAUGHLIN.

located in the hori- 

